Thread: 93 Hard Dash, Spark Plugs and Fuses

Originally Posted by superquag

Is there any such thing as a re-mapped chip that can be simply dropped in/replaced into the ECU ? - Or does each one have to be set up for that car in that place with your mouth held in THAT way...?

Any alteration over the standard one would have to be an improvement...

Occasionally I've seen 19 litres/100km

I'm sure when they were new and working to spec a generic chip would have predictable results. But 20+ years on these will all now have unique issues which will require individual attention to sort out.

But this stuff is all DIY level now. Apart from removing glued and soldered-down chips from the original circuit board. I was able to barter with a very talented electronics tech for that one.

Roverguage, an AF gauge-set, a chip-burner and chips is about $300 all up. Software (tunerpro, 14CUX XDF and 14CUX toolkit) are all free.

I still don't know where the fuel consumption is at. It will (hopefully) be some time before I get through a few tanks and establish a new average.

Today was all foggy, cold and miserable (high of 3 degrees C) so an ideal day to sit inside a V8 rangie with the heater blasting.

Took it up a hill to get above the fog (~300m thick) and found more high cloud above obscuring the sun. But that was just the warmup. The actual job today was logging the air/fuel ratio across as many data points as possible.

I setup roverguage in the passengers seat to display the fuel table cell currently being used and printed out a spreadsheet of the current fuel map with space under each cell to write the current A/F reading.
My lovely (but reluctant) assistant had the job of logging as I drove. Juggling a laptop and a clip-board.

Now automatics are a PITA for this. Try as you might to get a specific load/rpm point and you can't. It'll change down and you're off into a whole nother part of the map.
But I decided that doesn't actually matter. If I can't purposefully get into those parts of the map, then I shouldn't accidentally be in them either and whatever is there can do just fine.

The operating range is a big swoop from idle with 25-38% load going to a bit over 3000rpm. More throttle (higher load) is required to get more rpm so that whole upper right part of the map isn't accessible.
On the bottom left I found it similarly impossible to get a full load reading at 2000rpm. I could get into full load only at 2,700-3,100 and of course to the rev-limit.

I found big lean spots (~15.5:1) at about 3000rpm at full load, higher was around 13:1. Interestingly at this 3000rpm point I'm now instructing the injectors to be fully open (255 on a scale of 0-255).

I'm working on a tuning theory of ~13.5:1 at low load (idle), 16:1 (lean cruise) for low load at 1500-3000rpm. Stoich by about 75% load and tapering to ~12.5:1 at full load.
We'll see how I go.

As well as correcting the values I have, I'm doing a lot of smoothing in between. There are some very strange dips and peaks which I'm hoping were related more to Pommy emissions tests than engine needs.

Just back from a test-drive and this is quite good.

I have lean cruise (~16:1) from 80-100km/h where it's needed.
I have stoich at slightly higher load and a solid 12.5:1 under hard acceleration.

It's now snarling when you give it the boot and picks up speed like a V8 should. I may have woken up all of the original 190 horses.

But most importantly. I've now got over 270km on this tank (tank is dented, only takes ~55 litres from fuel light) and the light isn't yet on.
Meaning even with all the short and hard test running it's less than 20L/100km.

Filled today. 54.3 litres for 312km. So a bit under 6km per litre. That's the last of the short run testing and awful rich tunes.
This next tank will be the first with a proper tune.

Interestingly the tune is still settling in. Particularly the full load values are still bouncing around a little. It had richened up around 3700rpm and leaned out towards 5000rpm.
I don't know if my injectors are cleaning themselves a bit or what but this shift and the correction will fix a funny step I had in the fuel map.

So how many litres does everyone else get in once the fuel light comes on? I get about 65 litres in my 85, but it has the steel tank and the sender has been screwed with.

Very interesting work mate. Well done on the detail

you need to split all this fault finding of the mixtures out of here and place it under it's own thread so poeple can find it!

Originally Posted by DoubleChevron

you need to split all this fault finding of the mixtures out of here and place it under it's own thread so poeple can find it!

Once I know it's good, I'll see what I can do. Full load figures are still bouncing around a little. Possibly weather related.

So now it's running right, I should probably look after it. Is Ryco Z89A (or equivalent) the right filter? Search Part : Ryco Oil Filter | Z89A Oil Filter | LANDROVER DISCOVERY :: Ryco Filters :: Automotive Filters Australia
Any objection to running 15w40 diesel engine oil in it?

I've called the tune good. ECU is now screwed back together and bolted back down where it should be.
I had to reset the idle. This was so easy with Rovergauge giving control of the stepper motor.

1. Turn the key on and connect roverguage.
2. Select stepper motor control and close the valve.
3. Unplug the stepper so it remains shut.
4. Start the engine and turn the 3/16" allen screw on the throttle body until engine rpm matches the rpm commanded by rovergauge. This was 730rpm in my case, a full two turns on the screw since the last attempt.
5. Reconnect the stepper motor plug.

Then enjoy your new stable idle.

Without rovergauge you have to physically remove and block the bypass hose at both sides. You also have to take a stab at the commanded rpm and find an accurate independent way to measure engine rpm.